Metaphysics, a combination of the words Metá (meaning transcendent over) and physiká (physics), is a lively branch of philosophy that specializes in the study of existence and the nature of being. It has its origins in Aristotelian Greek philosophy and is still very much debated and discussed by contemporary philosophers today.
It is important that metaphysics is not confused with science. Although it has “physics” in its name, metaphysics deals with questions beyond the scope of the sciences (physics, cosmology, chemistry, biology, sociology, anthropology, etc.). This is not to say that there is no relationship between science and metaphysics. In fact, there is. Cosmogony, the branch of metaphysics that studies the beginning of the universe, for example, can be informed by scientific findings such as in physics and Big Bang cosmology, and so on. However, the questions metaphysicians ask, such as: Was there a transcendent cause to the Big Bang? What was the nature of this cause? Did time exist before the Big Bang? etc., are not scientific ones and cannot be settled by appeal to science itself.
A key assumption the metaphysician makes is that reality is absolute, namely, that existence exists. This is an axiomatic principle that posits a reality existing independent of the human mind and thought. This reality is objective because persons do not invent it; rather persons discover and interact with it. Moreover, metaphysicians assume that they can know things about this reality and that the questions they ask and attempt to answer are in some way reflective of it. For the metaphysicians, the more we know about reality the better off we are for a number of reasons. Metaphysics asks thoughtful questions that grapple with the nature of reality itself. These questions are significant for many topics people view as important, especially religious and theological ones. The way many view God, for instance, will depend on the conclusions drawn from topics metaphysics engages.
Metaphysics can be broken down into various branches asking important questions. First, cosmogony studies the metaphysical implications of the beginning to the physical universe of space and time. It asks questions related to causation: What caused the universe? And can we know about this cause? Second, questions related to free will and determinism. Given developments in the science of psychology and the hard sciences, especially neuroscience, can modern persons still hold to the reality of free will? Or should free will not exist and determinism be true, then what implications would this have for human beings? Third, metaphysics engages the concepts of space and time. Why does space have three dimensions and not five or seven? Is space even a real thing or a substance? Does it exist independently of human beings? What about time? Does time actually exist? Most philosophers hold to two theories of time: A and B theory which hinge on the question of whether or not time an illusion or if it is really structured in a past/present/future continuum (the realist position). Fourth, there are questions relating to the mind. For example, does the universe really exist independently of one’s own mind? Or, given that the mind produces an image of what we perceive to be the universe “out there”, is my minding merely creating a convincing illusion? Moreover, do minds exist other than my own? Fifth, there are questions of ontology, which is the study of the nature of being. What can we know about certain entities? What are their natures and characteristics? What are the differences between physical and non-physical entities? And can we categorize entities into classes to better understand them? Sixth, some metaphysical questions are theological in nature. Questions pertaining to the nature of God and divine beings are discussed and debated. For example, does God or a god exist? What are the arguments for and against the existence of God? What are the implications for human beings if God does not exist? How does an immaterial entity relate to and interact with physical creation? Can a being that is omnipresent (existing in all places at once) exist? As becomes evident, many such questions can be asked and debated in great detail.